you can now update your Ace Combat Assault Horizon Enhanced Edition for PC game to replace the Games for Windows Live functionalities with Steamworks functionalities.
The update is available from today – February 24th and will let you keep both your saves and achievements.
Please visit http://steamcommunity.com/app/228400/discussions/ to read the update process.

If you played or are currently playing Ace Combat Assault Horizon, you will be able to update and keep your achievements and saves between February 24th and April 1st.
From April 1st, the new version using Steamworks functionalities will become the default version of the game.

Please read the process below to update your game properly.
Please note that after April 1st, we won’t be able to guarantee your save files and achievements will be properly transferred.

You purchased a Game for Windows live version from a retailer (Disc) or Game for windows live marketplace (Digital)
1) We recommend that you add it to you Steam account using your serial
2) Launch the game and connect to Game for Windows Live. You will be asked to update the game (Title Update). Accept the update request.
3) Run the game, only currently signed user progress can be transferred to Steam.
4) Close the Game for windows live
5) Once the game is patched, click right on your game in the Steam library, go into properties, check that the BETAS tab is set to “Acah-2.0-“
6) Launch Ace Combat Assault Horizon EE v2.0 from Steam
7) The game will look for previous saves (and will only access them if you have updated through GfWL first). If saves and achievements are detected in your computer, it will ask to import them, click yes, and you are ready to go.

You purchased a Game for Windows live version from Steam
1) Launch the game and connect to Game for Windows Live. You will be asked to update the game (Title Update). Accept the update request.
2) Run the game, only currently signed user progress can be transferred to Steam.
3) Close the Game for windows live
4) Once the game is patched, click right on your game in the Steam library, go into properties, check that the BETA tab is set to “Acah-2.0-“
5) Launch Ace Combat Assault Horizon EE v2.0 from Steam
6) The game will look for previous saves (and will only access them if you have updated through GfWL first). If saves and achievements are detected in your computer, it will ask to import them, click yes, and you are ready to go.

CASE 2: You purchase Ace Combat Assault Horizon Enhanced Edition between February 24th and April 1st

1) Once the game is downloaded, right click on your game in the Steam library, go into properties, check that the BETA tab is set to “Acah-2.0-“
2) Launch Ace Combat Assault Horizon EE v2.0 from Steam